* {
  margin: 0px;
  
  font-family: Arial, sans-serif;
}

body{
  background-color:rgb(255, 252, 252);
}

#top {
  position: fixed;
  color: aliceblue;
  background: url(headbg.png);
  margin-left: -8px;
  height: 190px;
  width: 100%;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

#top_left{
  height: 200px;
  width: 35%;
}

#top_center{
  height: 200px;
  width: 30%;
}

#top_right{
  height: 200px;
  width: 35%;
}

#top_left_top{
  height: 30%;
  width: 100%;
}

#top_left_bottom{
  height: 55%;
  width: 100%;
}

#top_right_top{
  height: 30%;
  width: 100%;
}

#top_right_bottom{
  height: 55%;
  width: 100%;
}

#top_left_top_ul{
  margin-top: 20px;
  margin-left: 10px;
  display: flex;
  list-style-type: none;
  gap: 15px;
}

#top_left_bottom_ul{
  font-size: 25px;
  margin-top: 20px;
  margin-left: 10px;
  display: flex;
  list-style-type: none;
  gap: 40px;
}

#top_right_top_ul{
  margin-top: 20px;
  margin-left: 65px;
  display: flex;
  list-style-type: none;
  gap: 22px;
}

#top_right_bottom_ul{
  font-size: 25px;
  margin-top: 20px;
  margin-left: -25px;
  display: flex;
  list-style-type: none;
  gap: 40px;
}

.content {
  height: 1500px;
}

img{
  max-width: 100%;
  transition: transform 1s ease;
  transform-origin: top center;
}

.dropdown {
  position: relative;
  display: inline-block;
}

.dropdown-content {
  display: none;
  position: absolute;
  background-color: #f9f9f9;
  min-width: 160px;
  box-shadow: 0 8px 16px 0 rgba(0,0,0,0.2);
  z-index: 1;
}

.dropdown:hover .dropdown-content {
  display: block;
}

.dropdown::before {
  content: "\\25BC"; /* Unicode箭头符号 */
  position: absolute;
  left: -20px; /* 调整箭头位置 */
}